Triethylamine → (2R,3S,5S)-5-Formyl-3-isopropyl-2-[4-methoxy-3-(3 methoxy-propoxy)-phenyl]pyrrolidine-1-carboxylic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

Using SO3/pyridine complex: A solution of 4.7 g of alcohol 6 in 58 ml of methylene chloride is treated with 33 mL of dimethylsulphoxide and 5.67 g of triethylamine is added. The mixture is cooled to 0° C. and a solution of 6.84 g of the SO3/pyridine complex dissolved in 46 mL of dimethyl sulphoxide is added dropwise within 20 minutes. The reaction is stirred at 0° C. for 2 hours and quenched with 105 mL of water and 105 mL of heptane. The organic layer is separated and washed with 25 mL of 10% aqueous sodium hydrogen sulphate solution. The organic phase is then washed with 110 mL of water followed by 25 mL of saturated aqueous sodium hydrogen carbonate solution. Finally the organic phase is washed with water until the pH of the aqueous solution is 7. The solvent is then removed to give the aldehyde 7 as an oil. A negative [a]d is found at c=1, CHCl3. 1H-NMR (d6-DMSO, 300K) 9.75 (1H), 6.90-6.80 (3H), 4.63-4.30 (3H), 4.00 (2H), 3.75 (3H), 3.50 (3H), 3.23 (3H), 2.10-1.90 (4H), 1.85 (1H), 1.60 (1H), 1.05 (9H), 0.85 (6H).

Provenance & Evidence